As is known in the art, it may be necessary to control or adjust optimal signal levels applied to certain electronic devices or components, such as radio transceivers, as well as to ensure that the specified power is transmitted from the system. Variable attenuators can be used for such purposes. However, conventional signal attenuators may introduce detrimental phase shifts and signal reflections.
Phased array radars typically use thousands of radiating elements behind which other circuitry can be located, such as amplifiers, phase shifters, attenuators, low noise amplifiers (LNAs), RF switches, etc. Components can be integrated into a common enclosure containing both transmit and receive circuitry. Know attenuators for such circuitry include voltage or current control for biasing components to obtain a desired signal attenuation level. Some conventional current or voltage controlled adjustable-type attenuators produce a variable insertion phase that varies with attenuation level due to the varying reactive effects of the control transistors or diodes used within the attenuator devices. This insertion phase may be sufficiently large so as to impact performance of the attenuator and degrade performance of the antenna.